The purpose of these studies is to acquire basic information concerning the biochemistry, ultrastructure and formation of actin-containing filaments and filament bundles in non-muscle cells. Furthermore, to elucidate the factors which potentiate the formation of filament bundles and the possible roles of constituent proteins in bundle formation will be investigated. BIBLIOGRAPHIC REFERENCES: Edds, K.T. 1977. Initiation of Filament Bundle Formation. Biophysical Journal 17(2): 271a (abstract). Edds, K.T. 1977. Dynamic Aspects of Filopodial Formation by Reorganization of microfilaments. J. Cell Biol. 73: in press.